An organic light-emitting diode (OLED) device is manufactured by building up a series of layers, usually comprising an active or organic layer sandwiched between an anode and a cathode. A voltage is applied across the anode and cathode using contact pads arranged along one or more sides of the device, while the remainder of the device is encapsulated to protect the active layer from moisture. An OLED device can be top-emitting and/or bottom-emitting, depending on whether one or both of the electrodes are transparent. For example, for a bottom-emitting device, a transparent anode can be applied onto a transparent carrier such as glass using a layer of a transparent conducting oxide (TCO), for example indium tin oxide (ITO). The organic layer and the cathode are then applied onto the anode before the device is finally encapsulated. However, a transparent electrode is generally also associated with a poor lateral conductivity. As a result, the brightness over the light-emitting area in such a prior art OLED can noticeably drop off towards the centre. For OLEDs used in illumination applications requiring a homogenous brightness over the light-emitting area, this problem is usually circumvented by an additional structure of thin metal shunt lines applied onto the transparent electrode in order to enhance its conductivity. However, these shunt lines are limited in dimension in order to remain invisible from a certain distance.
Other types of OLED devices can comprise distinct regions, each with their own anode and/or cathode, so that each region is separately addressable. Such devices can be used to render images or patterns. However, the manufacture of such OLED devices is complex and cost-intensive, since one or more of the anode, active layer and cathode must be applied in a structured fashion, for example using photolithography or laser ablation, to obtain the desired structure.
It is therefore an object of the invention to provide a more economical OLED device and a more versatile OLED lighting arrangement.